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   <img id="left" src="images/asteroid-texas.jpg" alt="Asteroid" title="Asteroid as big as Texas!"/>
	
	<b>Asteroids</b>
	<p>
	Our understanding of asteroids is growing every day. The area between Mars and Jupiter is said to be the main location of asteroids. This area is called the asteroid belt. In this area asteroids travel together in an orbit around the Sun. Scientists say there are millions of asteroids located in the asteroid belt. Some asteroids have escaped this belt and can be seen traveling in the solar system, many seen with space probes and Earth telescopes. Many asteroids are made of resources important to us on Earth. Most asteroids are between 100 meters and 1 kilometer in diameter. Asteroid characteristics include rotation, size distribution and surface features. Scientists report that asteroids whose diameter is greater than 100 meters have a rotation no less than 2.2 hours. The composition of asteroids varies greatly. 
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	Ceres is a large asteroid that is approximately 623 miles in diameter - this is almost the size of Texas! 
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	Most asteroids are smaller, many of which are small fragments of carbon-based material. The recent studies of asteroids reveals that asteroids are not barren rocks as once believed. Instead, scientists have discovered that asteroids contain water on the surface in the form of ice. 
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 	 <img id ="left" src = "images/asteroid-ii.png" alt="Asteroid" title="Asteroid"/> 	
 	 <img id="right" src="images/300x300-williamette-meteorite.png" alt="Williamette Meteorite" title="Williamette Meteorite"/>
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	<p><b>Near Earth Asteroids</b><p>
	An Astronomical Unit (AU) is a unit of measure used to describe the distance between objects in space. One astronomical unit is the distance between the Earth and the Sun. A near-Earth asteroid spends its time between .93 and 1.3 AUs from the Earth. Most of the asteroids found in near-Earth orbit were once a part of the main belt. Each year scientists discover more asteroids in near-Earth orbit. There are approximately 9,000 asteroids located in near-Earth orbit. Some near Earth asteroids are outside of Earth's orbit;  there are some that are called <i>Earth-Crossers</i>. Earth-Crossers orbits intersect the orbit of Earth.
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	 Meteorites appear as a bright-lit objects and can be composed of heavy metal such as iron, as seen in the photo of the Williamette meteorite (right), made of iron and nickel. It was found in the United States northwest, in the Williamette Valley of Oregon.<a href="http://en.wikipedia.org/wiki/Willamette_Meteorite">Willamette Meteorite</a>
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            <p>Asteroids are interesting pieces of rock and rocky metal flying objects traveling throughout our solar system.  They come mainly from orbit between Mars and Jupiter. Sometimes they enter Earth's atmosphere and land on the ground, or burn and fall apart before hitting the ground.</p>
          
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